This invention relates generally to circuits which monitor the voltage stress in a capacitor, and more particularly to circuits which provide voltage stress indication signals in response to a capacitor's voltage history.
Known capacitor voltage stress systems of the type which indicate whether a predetermined permissible voltage for continuous operation has been exceeded, do not permit the full operational utility of the capacitor to be exploited. This results from the fact that such systems produce overstress indications, and trigger the operation of safety circuitry, only as a function of capacitor voltage. However, it is known that capacitors can withstand substantially higher voltages than their continuous operation voltages for short periods of time. Thus, capacitor failure resulting from voltage stress is a function of voltage and time.
It is, therefore, an object of this invention to provide a circuit for monitoring and indicating the true voltage stress of a capacitor.
It is a further object of this invention to provide a circuit for monitoring the voltage stress of a capacitor with respect to its voltage history.
It is another object of this invention to provide a system for disconnecting a capacitor from a source of electric potential in response to the amplitude and duration of a signal at the capacitor.